/**
 * The parent class of state
 */
public class ShopState implements IShopState {
	public ShopState() {
	}

	public void shop() {
	}

	public void generateBill() {
	}

	public void pay() {
	}

	protected void changeState(ShopContext c, ShopState s) {
		c.changeState(s);
	}
}